Purpose: To develop a deep learning model classifying the laterality of optical coherence tomography (OCT) images. Methods: The study included two-dimensional OCT images (horizontal/vertical macular section) from Seoul National University Hospital. A deep learning model based on ResNet-18 was developed and trained to classify whether OCT images were horizontal or vertical sections and to predict the laterality of the images. Analysis of the results included calculating a mean area under the receiver operating characteristic curve (AUROC) and evaluating accuracy, specificity, and sensitivity. Gradient-weighted class activation for mapping visualization highlighted critical regions for classification. Results: A total of 5,000 eyes of 2,500 patients (10,000 images) was included in the development process. The test dataset consisted of 1,000 eyes of 500 patients (590 eyes without macular abnormalities, 208 epiretinal membranes, 111 age-related macular degenerations, 56 central macular edemas, 23 macular holes, and 12 other macular abnormalities). The deep learning model predicted the OCT section of the eyes in the test dataset with a mean AUROC of 0.9967. The accuracy, sensitivity, and specificity were 0.9835, 0.9870, and 0.9800, respectively. The model predicted the laterality of the eyes in horizontal OCT images with a mean AUROC of 1.0000. The accuracy, sensitivity, and specificity were 0.9970, 1.0000, and 0.9940, respectively. Using vertical OCT images, deep learning models failed to demonstrate any predictive performance in laterality classification. Conclusions We developed a deep learning model to classify the horizontal/vertical sections of OCT images and predict the laterality of horizontal OCT images with high accuracy, sensitivity, and specificity.

Background: To investigate the association of glycemic control and retinal microvascular changes in patients with type 2 diabetes mellitus (T2DM) without diabetic retinopathy (DR). Methods: This retrospective, observational, cohort study included patients with T2DM without DR. The patients were categorized into intensive control (IC; mean glycosylated hemoglobin [HbA1c] ≤7.0%) and moderate control (MC; mean HbA1c >7.0%) groups. Optical coherence tomography (OCT) and swept-source OCT angiography (OCTA) image parameters were compared between three groups, including healthy controls. Results: In total, 259 eyes of 259 participants (88 IC, 81 MC, and 90 controls) were included. The foveal avascular zone area was significantly larger in the MC group than IC and control groups (all P<0.05). The IC group had lower vessel density in the superficial retinal layer and deep retinal layer than the controls (all P<0.05). The choriocapillaris (CC) flow deficit (FD) was significantly greater in the MC group than in the IC and control groups (18.2%, 16.7%, and 14.2%, respectively; all P<0.01). In multivariate regression analysis, CC-FD was associated with the mean HbA1c level (P=0.008). There were no significant differences in OCT parameters among the groups. Conclusion OCTA revealed that early CC impairment is associated with HbA1c levels; the CC changes precede clinically apparent DR. The OCTA parameters differed among the groups according to the degree of glycemic control. Our results suggest that microvascular changes precede DR and are closely related to glycemic control.

Purpose: To report a case of full-thickness macular hole (FTMH) formation secondary to demarcation laser retinopexy in a retinal break with localized retinal detachment patient.Case summary: A 59-year-old male visited our clinic with ocular discomfort in both eyes. Uncorrected visual acuity (UCVA) was 0.63 in right eye. Large retinal break in 1:30 o/c, localized retinal detachment and laser marking scars all around the right eye were found in fundoscopic exam. Posterior-vitreous detachment or vitreomacular traction was not observed in optical coherence tomography (OCT). Demarcation laser retinopexy was performed around the margin of retinal detachment and peripheral degenerative lesions. Three months after demarcation laser retinopexy, UCVA in right eye of the patient was decreased to 0.16 and full thickness macular hole was observed on OCT examination. Pars planar vitrectomy, internal limiting membrane peeling, and SF6 gas tamponade were performed in the right eye. One month after the surgery, closure of FTMH was observed. Three months after surgery, there were no recurrence of FTMH in the right eye. Conclusions Demarcation laser photocoagulation of localized retinal detachments may predispose to FTMH formation. Even though it can be occurred rarely, follow-up check-up is necessary in consideration of the possibility of FTMH, which can cause serious visual loss.

Purpose: To develop a deep learning model that can predict the axial lengths of eyes using ultra-widefield (UWF) fundus photography. Methods: We retrospectively enrolled patients who visited the ophthalmology clinic at the Seoul National University Hospital between September 2018 and December 2021. Patients with axial length measurements and UWF images taken within 3 months of axial length measurement were included in the study. The dataset was divided into a development set and a test set at an 8:2 ratio while maintaining an equal distribution of axial lengths (stratified splitting with binning). We used transfer learning-based on EfficientNet B3 to develop the model. We evaluated the model’s performance using mean absolute error (MAE), R-squared (R2), and 95% confidence intervals (CIs). We used vanilla gradient saliency maps to illustrate the regions predominantly used by convolutional neural network. Results: In total, 8,657 UWF retinal fundus images from 3,829 patients (mean age, 63.98 ±15.25 years) were included in the study. The deep learning model predicted the axial lengths of the test dataset with MAE and R2 values of 0.744 mm (95% CI, 0.709–0.779 mm) and 0.815 (95% CI, 0.785–0.840), respectively. The model’s accuracy was 73.7%, 95.9%, and 99.2% in prediction, with error margins of ±1.0, ±2.0, and ±3.0 mm, respectively. Conclusions We developed a deep learning-based model for predicting the axial length from UWF images with good performance.

The purpose of this study was to compare the effect of sodium fluoride(NaF) varnish and potassium iodide(KI) on remineralization efficacy of silver diamine fluoride(SDF) by measuring microhardness and evaluating surface morphology by scanning electron microscope(SEM).
Artificial caries lesions were induced on extracted primary molars and vickers microhardness was measured. Specimens were randomly separated into 4 groups for treatment. The specimens in group I were treated with SDF, group II with NaF varnish after SDF, group III with KI after SDF and group IV with distilled water. After 8 days of pH cycling, vickers microhardness was measured and difference before and after treatment was calculated. For SEM, 2 samples were evaluated respectively after enamel polishing, lesion formation and after pH cycling.
Group III showed highest increase in microhardness. Group I showed higher increase in microhardness than Group II but without statistical difference. Group IV showed lowest increase in microhardness value among 4 groups.
On SEM image, group I, II and III showed smoother and less irregular surface compared to group IV. Amorphous crystal pellicles were observed in group III.
In conclusion, SDF, SDF and NaF, SDF and KI groups showed smoother surface and increase in microhardness suggesting the possibility that remineralization effect might take place in oral conditions. In addition, in limited conditions of this study, applying NaF varnish after SDF did not increase the remineralization efficacy of SDF while KI significantly increased the remineralization efficacy of SDF. However, additional study considering various conditions that might affect demineralization and remineralization in clinical situations need to be conducted.

The aim of this study was to compare compressive strength and microhardness of recently introduced alkasite restorative materials with glass ionomer cement and flowable composite resin. For each material, 20 samples were prepared respectively for compressive strength and Vickers microhardness test. The compressive strength was measured with universal testing machine at crosshead speed of 1 mm/min. And microhardness was measured using Vickers Micro hardness testing machine under 500 g load and 10 seconds dwelling time at 1 hour, 1 day, 7 days, 14 days, 21 days and 35 days. The compressive strength was highest in composite resin, followed by alkasite, and glass ionomer cement. In microhardness test, composite resin, which had no change throughout experimental periods, showed highest microhardness in 1 hour, 1 day, and 7 days measurement. The glass ionomer cement showed increase in microhardness for 7 days and no difference was found with composite resin after 14 days measurement. For alkasite, maximum microhardness was measured on 14 days, but showed gradual decrease.

Background and Objectives: The nucleotide-binding oligomerization domain-like receptor (NLRP) 3 is known as a member of the NLR family, and it has been confirmed that the NLRP3 inflammasome is associated with various diseases such as asthma, inflammatory bowel disease, metabolic disorders and multiple sclerosis, as well as other auto-immune and auto-inflammatory diseases. However, the role of NLRP3 in chronic rhinosinusitis with nasal polyps (CRSwNP) has not yet been explored.Subjects and Method Forty-four specimens of nasal polyps and 25 specimens of uncinate processes were collected from patients with chronic rhinosinusitis with nasal polyps, and 25 specimens of uncinate tissues were collected from patients who underwent other rhino-surgeries. The western blot assay was employed to analyze the expression of NLRP3; interleukin (IL)-1β and IL-17A were detected using immunohistochemistry and real-time polymerase chain reaction. The production of lipopolysaccharide (LPS) induced IL-1β and IL-17A with or without the NLRP3 inflammasome inhibitor (MCC950) was measured using an enzyme linked immunosorbent assay in cultured dispersed nasal polyp cells. Results: NLRP3 showed a high level of expression in nasal polyps than in the control group (p<0.01). The expression of IL-1β and IL-17A was significantly higher in nasal polyps in the CRSwNP group than in the control group (p<0.05). LPS-induced production of IL-1β was significantly suppressed by treatment with the NLRP3 inflammasome inhibitor (p<0.05). Conclusion The NLRP3 inflammasome plays an essential role in the pathogenesis of CRSwNP, and thus MCC950 can be considered a prospective therapeutic for NLRP3 inflammasome-mediated inflammation in nasal polyps. Our data provide new evidence that IL-17A is involved in inflammasome-associated inflammation in nasal polyps.

Langerhans cell sarcoma is a rare, proliferative tumor of Langerhans cells, which shows cytologic characteristics and clinical features of malignant tumor. Langerhans cell sarcoma primarily occurs in lymph nodes, skin, lung, liver, and spleen. However, very few cases have been reported in the head and neck region. Because of its rarity, an optimal treatment approach is unknown; however, Langerhans cell sarcoma grows aggressively and shows a poor prognosis, such that a more aggressive and multi-modality treatment approach is necessary. Here, we report the case of a 36-year-old male with Langerhans cell sarcoma, who presented with a mass in the submandibular gland area and was treated with wide excision and postoperative radiotherapy.

Langerhans cell sarcoma is a rare, proliferative tumor of Langerhans cells, which shows cytologic characteristics and clinical features of malignant tumor. Langerhans cell sarcoma primarily occurs in lymph nodes, skin, lung, liver, and spleen. However, very few cases have been reported in the head and neck region. Because of its rarity, an optimal treatment approach is unknown; however, Langerhans cell sarcoma grows aggressively and shows a poor prognosis, such that a more aggressive and multi-modality treatment approach is necessary. Here, we report the case of a 36-year-old male with Langerhans cell sarcoma, who presented with a mass in the submandibular gland area and was treated with wide excision and postoperative radiotherapy.
Adult ; Head ; Humans ; Langerhans Cell Sarcoma ; Langerhans Cells ; Liver ; Lung ; Lymph Nodes ; Male ; Neck ; Prognosis ; Radiotherapy ; Sarcoma ; Skin ; Spleen ; Submandibular Gland

PURPOSE: The aim of this study was to investigate the incidence and associated clinical factors of delayed absorption of subretinal fluid (SRF) after surgery for rhegmatogenous retinal detachment. METHODS: This study involved 36 eyes of 36 consecutive patients who underwent successful surgery for rhegmatogenous retinal detachment. A complete ophthalmologic evaluation, including clinical fundus examination, optical coherence tomography, and indocyanine green angiography, was conducted before and after surgery. Delayed absorption was defined as the presence of residual concave SRF or an SRF bleb at 6 months after surgery. Clinical factors and choroidal features on indocyanine green angiography were compared according to the presence and absence of delayed absorption. RESULTS: Eighteen of 36 eyes (50%) showed delayed absorption. Macular involvement and worse preoperative visual acuity were significantly related to the presence of delayed absorption (p = 0.001 and p = 0.034, respectively). On indocyanine green angiography, preoperative choroidal vascular hyperpermeability was noted in 70% of eyes with delayed absorption and in 14% of eyes without it (p = 0.010). CONCLUSIONS: Delayed absorption of SRF after retinal reattachment surgery was not rare, with a 50% of incidence in this study. Macula-off status was significantly related to the incidence of delayed SRF absorption, and choroidal features such as choroidal vascular hyperpermeability might be responsible in part, possibly through the resultant exudative property of choroid.
Absorption* ; Angiography ; Blister ; Choroid* ; Humans ; Incidence ; Indocyanine Green ; Retinal Detachment ; Retinaldehyde* ; Subretinal Fluid* ; Tomography, Optical Coherence ; Visual Acuity